Add nickname package as INFERENCE

This should keep things more simple sometimes, as we
can call the whole package as inference.

(require :lisp-inference) # load system
(in-package :inference) # change package to namespace :inference alias

Author: ryukinix

src/package.lisp

@@ -39,4 +39,5 @@
    :make-disjunction
    :make-implication
    :make-biconditional
-   :*valid-operators*))
+   :*valid-operators*)
+  (:nicknames "INFERENCE"))